My most secure and memorable password is !@#$%^&*() Are these characters easy to forget when I use it in a password? Here are some tips for me to memorize these and many other special characters.

Remember them as numbers forget special characters
I was typing 123...0 on a qwerty keyboard with Shift key pressed. So, !@#$%^&*() is simply a combination of special characters created with plain numbers from my mind and ASCII keyboard.

Use position of characters in your password effectively.
Computer passwords are generally a combination of 8 or more characters. I select a particular position in the pass phrase to be special, using a special character in it. For example, if "password" is my password the letter "p" is at 1st, "a" at second and so on till 8. Choose one position (and be consistent across my passwords) say, position 5 to be always a special character, the letter "w" comes at 5th position, it must be replaced with a special character in this pass phrase, if I use the special character % instead of letter "w", the password will become "pass%ord" and my password became stronger than the plain dictionary word "password"

Utilize the flow of characters in strong passwords
Increment or decrement the character strength, say the word "password" in a an incrementing format, "passw0R$" started with plain English letters and ended with special letters. I can also use a combination of incrementing and decrementing the character strength.

Relate pass phrase to something which you only know in a specific format
Use a pass phrase that is made out of your unique mind. Start with my favourite person's last name, the places I lived and the place I always want to be. This is just an example and it must be something very unique for you.

Reverse the character positions with a twist
"drowssap" is a plain reversal of the word "password" how ever this is stronger than the plain "password" You may apply similar logic with combination of letters and numbers

Phone number and place
"N^@^@&Y" is a strong password I can remember if I can remember the phone number 624627 New York (NY) You can follow this combination if this makes sense to you

Relate to the place you use
Is you are using a password at PasswordBB.com relate its purpose and use it in your password, say "Security Essentials" is the context you may consider using here

One special unique number
My google.com password is "password5", my facebook.com password is "password8" a number at the end, did you get it? number of letters in that domain is used as the last password character. You may use different positions like start, second, second-last or at the end. For remembering the position, be consistent with it.

Names of food items
Use combinations of food item names or brand names. This must be something unique and how many of it you can have it at a time can be the number you can attach to your strong password. Example. 2McFeast@Lunch

Anything you can easily remember with a twist
Use combination of things with twist it in, replace English alphabets with similar special characters, for example the pass phrase "password" can become, "p@$$w0rd" a->@ s->$ and o->0